RFR: 8313882: Fix -Wconversion warnings in runtime code [v2]

[Patricio Chilano Mateo]

On Wed, 9 Aug 2023 16:40:32 GMT, Coleen Phillimore <coleenp at openjdk.org> wrote:

>> There was a reason that c had to be an int.  Now I'll have to rebuild and figure it out again.
>
> No, it works and is a bit better, so I made this change.

I see error in some builds due to the EOF comparison though now that c is a char. I think Dean was suggesting doing the cast inside the loop.

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/15177#discussion_r1289124669